Google PageRank has a few less secrecy in a session of Q & A group of Google Webmaster Help held in the last days of October, Matt Cutts, Mail Ohye and other Google-man responded to the questions of users and (just) the webmaster spigolose some questions about how to ranking web pages used on system most famous mathematician of the Internet.

The session did not lead to the publication of anything transcendental or PageRank is also in itself a carrier of universal truth unknown to most people, that is a trademark patented and documented. But the responses collected are used to dissolve some doubts about what really counts to climb the rankings of approval of the mega-cervellone mathematical Google. And to help generate other, to put it across.

Among the more interesting responses there is such as to ensure the maintenance of the PageRank of the pages in case of errors HTML 301, namely a permanent redirect the URL to a new destination. PageRank remains the same even if redirect recursive, but whereas the standard HTML 1.0 will grant up to 5 in the series is not to exaggerate the case.

The PageRank is then calculated differently in each language ecosystem when the content is translated, say the people of Google, and this will probably not be a Q & A to dispel any doubts about that. The search algorithm in the indices of Mountain View is changed often? And how often? “Both” is the predictable response, last year, tweak it amounted to more than 450.

Count the speed with which a page is loaded in the calculation of PageRank? Yes, probably counts a lot, even if the Google-man does not say so explicitly. Like say, between the lines, that if a blog post has many comments is ranked first in search results and links are not present on a site destination URLs of these links within varranno index calculated on based on PageRank.

Among the considerations are less clear there is the question of “if” and “if so, as” virtual age of a website influence its position in the research. In this case, the G-man first argue that ‘yes, if your domain has been credible for years it can help “and that buying a new domain, move their own content and hope to have the same PageRank is always mere utopia . Then, however, expressed as contradicting earlier revealed that “in most cases it does not matter, because we have the best information, not just those older.”

1. Purchase and request domain transfer at the new registrar

When you purchase a domain transfer, some of the registrars may let you to keep all the time remaining on your existing registration, plus you may get a FREE 1-year extension. After the payment is processed, the status of the domain at the new registrar will be set to Authorization Required. You will also receive an email from the new registrar containing Transaction ID and Security Code.

2. Request authorization code at current registrar.

Login to your current registrar account and request for “authorization code request”.  You have to turn off the domain protection before you can request authorization code from the current registrar. Following screen shows the link from my current registrar that gave the option to request authorization code.

3. Authorization code received from current registrar.

You’ll receive an email from current registrar with Authorization code.

We received your authorization code request on 07/02/2008
for your domain name thegeekstuff.com.
Your authorization code is: 12345678911

4. Begin the transfer from the new registrar using the authorization code.

Go to the new registrar and begin the transfer process. At this stage, the new registrar will display the Status as “Authorization required” and the Recommended Action as “Authorization - Begin transfer authorization”

Fig: Domain Status at new registrar before the transfer process

Enter the authorization code that was received from the current registrar and complete this process. After this step, the new registrar will display the Status as “Pending Current Registrar approval” and the Recommended Action as “Accept transfer at current registrar”

Fig: Domain status at new registrar after the transfer process is initiated

5. Email Notification from current registrar.

You will get an email from the current registrar confirming your transfer request. You don’t need to take any action if you want to accept the transfer. If you wish to cancel the transfer, follow the link from the email.

We received notification on July 1, 2008 7:21:44 PM EDT that you have requested to transfer
to another domain name registrar. If you would like to proceed with this transfer you do
not need to respond to this message. If you wish to cancel the transfer please contact
us before July 5, 2008 7:21:44 PM EDT by visiting our secure website https://

If we do not hear from you by July 5, 2008 7:21:44 PM EDT, this transfer will proceed.
We are committed to providing you with the solutions, services, and support to help

you succeed online. We hope to continue serving you in the future.

6. Domain Transfer completed to new registrar

A final confirmation email from new registrar was received approximately 4 days after initiating the transfer at the current registrar. Please note that the current registrar has up to 5 days to release the transfer of the domain

References:

ICANN - Internet Corporation for Assigned Names and Numbers, coordinates the domain name across the internet to make sure they are unique.  FAQ for Domain-Name Holders clarifies lot of questions about domain name transfer.

If you’ve transfered a domain name to a new registrar, please share your experience. If you are planning to transfer your domain name to a new registrar, what is your primary reason for transferring?

Source: http://www.thegeekstuff.com/2008/07/how-to-transfer-domain-name-to-new-registrar/

Step # 1: Login to sitemap account

At the top of screen you will see option to add site. Just paste URL of your blog (for example http://cyberciti.blogspot.com/)

(Click to enlarge image)

Click on Ok button. Next you will get confirmation message. Your site has been added to your account.

Step # 2: Now you need to verify your ownership of blog to view detailed statistics. Click on verify link. Google offers two methods of verification. You can either upload an HTML file with a name we specify (which is not possible with Google Blogger account), or you can add a META tag to your site’s index file. Adding META tag via template code is possible so just select Add a META tag from drop down menu:

(Click to enlarge image)

It will generate code for you, copy the meta tag and paste it into your blogger.com template section).

Step # 3: Go to your blogger.com and login to your account. Goto your blog > Click on Template

Paste the META tag code after section:

(Click to enlarge image)

Click on Save Template changes button

Click on Republish Index only button > Wait for few seconds so that your blog being published successfully.

Step # 4: Now goto sitemap account and click the box that read as follows:

I’ve added the META tag in the home page of http://cyberciti.blogspot.com/. Click on Verify button.

(Click to enlarge image)

Step # 5: Now your site is added to sitemap account and verification is done. Next you need to add actual sitemap url. Since blogger.com account don’t allow you to create a text file or anything else you need to add your site feed (ATOM xml) file as a site map. Click on add a sitemap link:

(Click to enlarge image)

Step # 6: You can add a Sitemap to your account to provide Google additional information about about your blog. Google will process your Sitemap and provide information on any errors in the Sitemaps tab as well your sitemap will be downloaded everyday to index your blog fast.

Select type as : Add General Web sitemap

Now you need to add Atom 0.3 feeds. Generally, you would use this format only if your site already has a syndication feed and this is the only way to add sitemap to your blogger.com account.

Paste url of your Atom feed: For example http://cyberciti.blogspot.com/atom.xml and click on Add Web sitemap:

Update: If you are using a new blogger beta system, use http://yourblogname.blogspot.com/feeds/posts/full as a feed url.

You will get confirmation:

You have added a Sitemap to http://cyberciti.blogspot.com/. Reports may take several hours to update. Thank you for your patience!

And you are done and your blog will be now index very fast (depend upon your posting and content).

Source: http://theos.in/

Does your web server support mod_rewrite?
Ensure that you are using Apache web server and mod_rewrite module is installed in your web server. To check this you can either contact your hosting service provider or check it yourself using these simple step.

Step1. Create a blank text file using notepad or any other editor.
Step2. Put in the file.
Step3. Save as ‘info.php’ [on windows Save as "info.php" (with double quotes)].
Step4. Upload the file to your web server’s root or any other folder.
Step5. Call the file in the url - http://your-domain.com/info.php and check if you see mod_rewrite in ‘Apache loaded modules’ section. If NOT, then please contact your hosting provider and request them to install/enable mod_rewrite.

Note: If you have access to your httpd.conf file, you may check for mod_rewrite in that file as well. And also your httpd.conf must be configured to allow Fileinfo override. Contact your hosting provider for any server related issues.
Next thing you would do is check your .htaccess file. Make a backup of your existing .htaccess file so that in case because of your changes if web server does not serve your site, you can always restore the backup copy.

Examples of mod_rewrite

1. Description - Your current pages are called using index.php with parameter of url i.e
http://www.example.com/index.php?url=category
and instead of this URL, you want a nice and easy to read URL like http://www.example.com/category
Solution - Put the following lines in your .htaccess file.
RewriteEngine on
RewriteRule ^([^/\.]+)/?$ /index.php?url=$1 [L]
Note: If your file already contains a line ‘RewriteEngine on’ then you don’t need to put it again unless it was set to off before you putting in your lines.

2. Description - Your current URL is
http://www.example.com/index.php?cat=category&subcat=subcategory
which you would like to see as
http://www.example.com/category/subcategory
Solution - Put the below lines in your .htaccess file
RewriteEngine on
RewriteRule ^([^/\.]+)/([^/\.]+)/?$ /index.php?cat=$1&subcat=$2 [L]

3. Description - You want to have many sub categories or categories like
http://www.your-domain.com/category/subcat1/subcat2/subcat3/subcat4/subcat5/
which you would to rewrite to
http://www.your-domain.com/index.php?cat=category&subcat1=subcat1&subcat2=subcat2 and so on …
Solution - See below lines..
domain.com/category –> index.php?cat=category
RewriteRule ^([^/\.]+)/?$ /index.php?cat=$1 [L]
domain.com/category/subcategory/ –> index.php?cat=category&subcat=subcategory
RewriteRule ^([^/\.]+)/([^/\.]+)/?$ /index.php?cat=$1&subcat=$2 [L]
domain.com/p1/p2/p3/ –> index.php?a=p1&b=p2&c=p3
RewriteRule ^([^/\.]+)/([^/\.]+)/([^/\.]+)/?$ /index.php?a=$1&b=$2&c=$3 [L]
domain.com/p1/p2/p3/p4 –> index.php?a=p1&b=p2&c=p3&d=p4
RewriteRule ^([^/\.]+)/([^/\.]+)/([^/\.]+)/([^/\.]+)/?$ /index.php?a=$1&b=$2&c=$3&d=$4 [L]

4. Description - Your URL has a folder and you would like rewriting for that folder. The URL looks like this http://domain.com/folder/index.php?url=name which you want to see as http://domain.com/folder/name/
Solution - Place the following lines in your .htaccess file
RewriteEngine on
RewriteRule ^folder/([^/\.]+)/?$ folder/index.php?url=$1 [L]

5. Description - Your actual URL is http://example.com/index.php?page=hello which you want to see as http://example.com/hello.htm
Solution - Place the following lines in your .htaccess file
RewriteEngine on
RewriteRule ^([^/\.]+).htm$ index.php?page=$1 [L]

6. Description - Your URL is http://example.com/folder/index.php?page=hello which you want to see as http://example.com/folder/hello.htm
Solution - Place the following lines in your .htaccess file
RewriteEngine on
RewriteRule ^folder/([^/\.]+).htm$ folder/index.php?page=$1 [L]
There are many more things that you can do with mod_rewrite. As and when I discover more examples, I will keep updating this page. Please feel free to post your usage of mod_rewrite if already not covered here and I will add them to the above list of examples.

Links for reference:
1. Apache Documentation
2. Wikipedia page for regular expression

Original source:
http://www.bloghash.com/2006/12/apache-mod_rewrite-examples/

With AdSense for Search now powered by Google Custom Search, professional web publishers have some truly advanced and very cool customization options to best monetize their search results pages through AdSense contextual ads.

Among some of the most powerful new customization options are a) keyword tuning, b) creating vertical search solutions, and c) customizing fully the placement of ads on your site Google search results pages.

The new Custom Search platform has significantly improved its indexing capabilities while fully integrating the power of AdSense for Search. AdSense web publishers like you can now create unlimited Custom Search Engines (CSEs) and take advantage of the most popular customization features already available within their AdSense accounts.

If you are not yet familiar with it, you should know that Google Custom Search is built on top of the very main Google index, though now it maintains its own index for enhanced coverage of sites included in CSEs. This improved indexing approach only affects search results within your custom-created search engine, not your own site rank and indexing level on Google.com.

Overview - AdSense for Search Integration With Custom Search

• Create a custom, personalized search engine in no time at all
• Customize the appearance of search results and ads
• Tune results and ads to your site’s content and audience
• Get more comprehensive site search results with improved indexing
• Earn revenue while helping your users find what they’re looking for

Key Features

• Site Search

  If you’ve worked hard to attract users to your site, so it’s understandable that you’d be concerned about those users leaving through web search. Now you can choose to provide just site search so users can find all the information they’re looking for on your site, and you can host the search results on your own pages so that they can find that information without leaving your site.

• Improved Indexing of your Pages

  Google has recently improved its indexing technology so that you can provide a more enhanced Site Search experience to your users. AdSense for search will now index even more pages of your site so that your users will see more results from your site in your AdSense for search results.

• Vertical Search

  You can also allow your users to search across multiple sites - this could be a network of sites that you own or other related sites that you think your users might find useful. If you write book reviews on your blog, for example, you can use vertical search to specify a list of online bookstores for users to search through. Other examples of vertical searches include computer forums, travel blogs, political sites you endorse, etc.

• Tuning Search Results and Ads with Keywords

  Search terms can have different meanings in different contexts, so you can now configure your search engine with relevant keywords. Let’s say you manage a site about yoga - you can enter keywords such as ‘yoga,’ ‘exercise,’ and ‘meditation’ so that when a user searches for ‘mat,’ the search results and ads will be more related to yoga mats and less to commercial floor mats. (You can see an example of this in the video below). In research experiments run so far it has been found that this tuning has led to an increase in earnings for web publishers.

• Choosing Ad Position

  Do you want your AdSense ads to appear at the top and bottom of your search results? Or along the right sidebar as well, just like on Google.com? Now you can make the call on where ads are placed. (Placing ads at the top and right monetizes the best for publishers.)

• Quick and Easy Changes and Modifications To Your Setup

  Just as you use Google ad management feature to quickly change the settings for your ad and referral units, you’ll be able to do the same for your search engine within your AdSense account. Your settings will be saved in your account, so you won’t need to generate new search code for each change.

Original posted by Robin Good on Wednesday, May 7 2008, updated on Wednesday, May 7 2008 under Creative Commons License

In this new Sharewood Guide I have collected the best free tools to convert any web page to RSS.

Web page to RSS converters are free tools, usually web-based, that anyone can use to keep changes of any site which doesn’t offer a RSS feed for its readers.

RSS feeds are very intuitive and easy-to-use: to create a feed just grab the desired page’s URL, paste it into the box, and click generate. Some of these tools, will also offer advanced options to let you refine which of the items present on a specific web page need to be included in your newly generated RSS feed.

Here the best web page to RSS converters I have found out there (if you know of other ones, please help me out by adding them in the comment area at the end):

Convert Web Pages Contents Into RSS Tool List

1. Dapper
   
   Dapper is a free service that lets you convert any web page content (from YouTube search results to blog posts) into a RSS feed in seconds. Just provide a URL (ore more), select and divide in multiple fields the content that you want to be included in your feed (e.g. titles, descriptions, images…), decide the output format and save your feed. You will need to be registered to create as many feeds as you want. Free.
   http://www.dapper.net/
2. Yahoo! Pipes
   
   Yahoo! Pipes is a RSS feed mixer that mashes content from the web together into new interactive creations. It lets you drag and drop different information feeds, such as the latest news items from your favorite news sources, or search queries, or anything else you want, and combine them through a series of filters into “pipes“.The service is completely free to use; a Yahoo! account is required.
   http://pipes.yahoo.com/
3. Feed43
   
   Feed43 is an online service that converts standard web pages or XML documents to RSS feeds. In order to create a new feed, simply identify the web page from which to generate a RSS feed, define the search patterns to help the system locate the news source, and generate the feed. The service is free to use, no registration is needed.
   http://www.feed43.com/
4. RSSxl
   
   RSSxl is an easy-to-use web page to RSS converter, that allows you to convert any page to a normal RSS feed. After you provide the URL of the site, you just have to identify the news items’ start and end points by pointing to them with some HTML or string keywords. Then you can click generate, and get your new RSS news feed to keep updated with that page’s changes. Free.
   http://www.wotzwot.com/rssxl.php
5. Web2RSS
   
   Web2RSS is a web-based app that automatically turns any website into a RSS news feed. Pasting the site’s URL is enough to let Web2RSS convert the content and export it in RSS format, without doing anything. If you want to make it even more precise, you can either match or exclude parts of the page using HTML or string expressions present on the page. Free to use, no registration is needed.
   http://www.baekdal.com/web2rss/
6. RSS Wizard
   
   RSS Wizard is a software for Windows machines than can generate the RSS feed out of any web page without having to edit it first. To create a feed, you have to start the program, paste a URL, provide a start and end string to make the software recognize where the news begin and end, and click OK to create the feed. Free to try, $29.05 to buy.
   http://www.extralabs.net/rss-wizard.htm
7. Feedity
   
   Feedity is an only feed builder that creates a RSS feed out of any website. Feedity is very easy-to-use and lets you get your feed in two steps: enter the URL of the desired website, help the service identify the news source on the page by pointing to some reference points (in simple or advanced mode), and click generate to retrieve your feed. Free to use, doesn’t require any registration.
   http://feedity.com/
8. Feedmarklet
   
   Feedmarklet gives you the ability to create your own RSS feed instantly through a browser bookmarklet, with no sign up required. After you insert a name for your feed, you can start adding content to it easily: find a link you want to keep an eye on and click on the bookmarklet button in your browser to immediately add the page you are on to your feed. By doing this, you can mix multiple sources into a single feed with one click. Free.
   http://www.feedmarklet.com/
9. FeedFire
   
   FeedFire is an HTML-to-RSS service allowing anyone to automatically create a RSS news feed for any website that does not have one. You simply register at FeedFire, input the URL of the page and it’ll do the rest for you in a matter of seconds. The service offers both free and paid feeds, which you can discover by signing up to the service.
   http://www.feedfire.com/
10. FeedYes
    
    FeedYes is a completely automatic tool for creating RSS feeds out of HTML web pages. Three steps are involved in the process: provide the URL of the page out of which you want to create a feed; indicate among the dynamic links found by FeedYes, which one is the first that refers to the news section; select the last item that closes the news section. Then, after a preview is shown, you can proceed and save your feed, or further refine it. Free.
    http://www.feedyes.com/
11. PonyFish
    
    Ponyfish is a web-based tool that allows you to create your own RSS feeds from almost any web page. All you have to do is point Ponyfish to the web page you want to create a feed from, then select at least two links that you will want to see in your feed (this indicates to the system which links are news sources) and finally copy your new RSS feed URL. Free to use, no registration needed.
    http://www.ponyfish.com/
12. Page2RSS
    
    Page2RSS is a completely web-based and automatic service which converts web pages to RSS feeds. You can just paste a page URL, and Page2RSS will instantly give you back a preview of the new RSS feed you just created, with the possibility of subscribing to it with the major RSS readers available. You can also use a toolbar button to create feeds for all the pages that you are currently viewing. Free to use, doesn’t require any registration.
    http://page2rss.com/
13. RSSpect
    
    RSSpect is a service that lets you add RSS feeds to any web page. RSSpect offers three kinds of feeds, so you can add a RSS feed to literally anything you find online: “AnySite feeds” allows you to create update feeds from any website or any document online, even those that you don’t control; “MySite feeds” allows you to generate advanced RSS feeds from your own website content, automatically. “Podcast feeds” are specially-designed RSS feeds to be used with iTunes. Free to use.
    http://www.rsspect.com/
14. CaRP
    
    CaRP is a PHP script that lets you generate RSS feeds for your web page. CaRP comes in two different versions: LE (basic) and Evolution (enhanced). The LE version allows no control on the appearance of your feeds, while the Evolution version comes with sixteen free bonus plugins to let you customize your RSS-generating experience: auto-update feeds, add images, embed videos, select which part of the text you want to show, sort your feeds, and much more. CaRP LE is free and CaRP Evolution is priced at $47. Registration required for both.
    http://www.geckotribe.com/rss/carp/

Originally written by Nico Canali De Rossi for MasterNewMedia and first published on October 13th 2008 as “Convert Web Pages Content Into RSS Feeds: Web Page To RSS Converters - Sharewood Guide“

http://www.webconfs.com/url-rewriting-tool.php

And now, an excellent beginner’s guide (with examples):

Until recently, I only had the vaguest of ideas of what mod_rewrite was, and I certainly had no clue about how to use it. So, when I started designing this site, I decided to delve into the wonders that are the mod_rewrite Apache module.

So, what is mod_rewrite for?

Simply, mod_rewrite is used for rewriting a URL at the server level, giving the user output for that final page. So, for example, a user may ask for http://www.somesite.com/widgets/blue/, but will really be given http://www.somesite.com/widgets.php?colour=blue by the server. Of course, the user will be none the wiser to this little bit of chicanery.

On workingwith.me.uk, I use mod_rewrite to redirect all pages to one central PHP page, which then loads the data that the user wanted from an external data file. Lots of people use mod_rewrite to show an “alternative” image when people are hotlinking directly to their images.

What do I need to get mod_rewrite working?

There’s pretty much only one thing you’ll need to get mod_rewrite working for you, and that’s to have the mod_rewrite module installed on your Apache server!

For the purpose of this article, I’m going to assume that you don’t have access to view or edit the Apache server httpd.conf file, so the easiest way to check whether the mod_rewrite module is installed will be to look on your phpinfo page. If you’ve not already created one of these for yourself, just copy and paste the following code into an new text file using your favourite text editor, save it as phpinfo.php, and upload it to your server:

<?php phpinfo(); ?>

Load that page up in your web browser, and perform a search for “mod_rewrite”. All being well, you’ll find it in the “Apache loaded modules” section of the page. If it isn’t there, you’ll have to contact your hosting company and politely ask them to add it to the Apache configuration.

Assuming the mod_rewrite module is loaded, then you’re good to go!

A simple mod_rewrite example

So, let’s write a simple mod_rewrite example. This isn’t going to be anything fancy; we’re just going to redirect people who ask for alice.html to the page bob.html instead. First, let’s create the Alice and Bob pages. Below is Alice’s webpage - create a similar one for Bob.

<html>
   <head>
      <title>Alice's webpage</title>
   </head>
   <body>
      <p>
         This is Alice's webpage
      </p>
   </body>
</html>

Upload both of these to your web server, and check that you can view both of them. Now comes the fun - we’re going to add a couple of lines to your .htaccess file. The .htaccess file is a text file which contains Apache directives. Any directives which you place in it will apply to the directory which the .htaccess file sits in, and any below it. To ours, we’re going to add the following:

RewriteEngine on
RewriteRule ^alice.html$ bob.html

Upload this .htaccess file to the same directory as alice.html and bob.html, and reload Alice’s page. You should see Bob’s page being displayed, but Alice’s URL. If you still see Alice’s page being displayed, then check you’ve followed the instructions correctly (you may have to clear your cache). If things still aren’t working for you, then contact your technical support people and ask them to enable mod_rewrite and the FileInfo override in their httpd.conf file for you

The structure of a RewriteRule

RewriteRule Pattern Substitution [OptionalFlags]

The general structure of a RewriteRule is fairly simple if you already understand regular expressions. This article isn’t intended to be a tutorial about regular expressions though - there are already plenty of those available. RewriteRules are broken up as follows:

RewriteRule

This is just the name of the command.

Pattern

A regular expression which will be applied to the “current” URL. If any RewriteRules have already been performed on the requested URL, then that changed URL will be the current URL.

Substitution

Substitution occurs in the same way as it does in Perl, PHP, etc.You can include backreferences and server variable names (%{VARNAME}) in the substitution. Backreferences to this RewriteRule should be written as $N, whereas backreferences to the previous RewriteCond should be written as %N.

A special substitution is -. This substitution tells Apache to not perform any substitution. I personally find that this is useful when using the F or G flags (see below), but there are other uses as well.

OptionalFlags

This is the only part of the RewriteRule which isn’t mandatory. Any flags which you use should be surrounded in square brackets, and comma separated. The flags which I find to be most useful are:

• F - Forbidden. The user will receive a 403 error.
• L - Last Rule. No more rules will be proccessed if this one was successful.
• R[=code] - Redirect. The user’s web browser will be visibly redirected to the substituted URL. If you use this flag, you must prefix the substitution with http://www.somesite.com/, thus making it into a true URL. If no code is given, then a HTTP reponse of 302 (temporarily moved) is sent.

A full list of flags is given in the Apache mod_rewrite manual.

A slightly more complicated mod_rewrite example

Let’s try a slightly more meaty example now. Suppose you have a web page which takes a parameter. This parameter tells the page how to be displayed, and what content to pull into it. Humans don’t tend to like remembering the additional syntax of query strings for URLs, and neither do search engines. Both sets of people seem to much prefer a straight URL, with no extra bits tacked onto the end.

In our example, you’ve created a main index page with takes a page parameter. So, a link like index.php?page=software would take you to a software page, while a link to index.php?page=interests would take you to an interests page. What we’ll do with mod_rewrite is to silently redirect users from page/software/ to index.php?page=software etc.

The following is what needs to go into your .htaccess file to accomplish that:

RewriteEngine on
RewriteRule ^page/([^/\.]+)/?$ index.php?page=$1 [L]

Let’s walk through that RewriteRule, and work out exactly what’s going on:

^page/

Sees whether the requested page starts with page/. If it doesn’t, this rule will be ignored.

([^/.]+)

Here, the enclosing brackets signify that anything that is matched will be remembered by the RewriteRule. Inside the brackets, it says “I’d like one or more characters that aren’t a forward slash or a period, please”. Whatever is found here will be captured and remembered.

/?$

Makes sure that the only thing that is found after what was just matched is a possible forward slash, and nothing else. If anything else is found, then this RewriteRule will be ignored.

index.php?page=$1

The actual page which will be loaded by Apache. $1 is magically replaced with the text which was captured previously.

[L]

Tells Apache to not process any more RewriteRules if this one was successful.

Let’s write a quick page to test that this is working. The following test script will simply echo the name of the page you asked for to the screen, so that you can check that the RewriteRule is working.

<html>
   <head>
      <title>Second mod_rewrite example</title>
   </head>
   <body>
      <p>
         The requested page was:
         <?php echo $_GET['page']; ?>
      </p>
   </body>
</html>

Again, upload both the index.php page, and the .htaccess file to the same directory. Then, test it! If you put the page in http://www.somesite.com/mime_test/, then try requesting http://www.somesite.com/mime_test/page/software. The URL in your browser window will show the name of the page which you requested, but the content of the page will be created by the index.php script! This technique can obviously be extended to pass multiple query strings to a page - all you’re limited by is your imagination.

Conditional Statements and mod_rewrite

But what happens when you start getting people hotlinking to your images (or other files)? Hot linking is the act of including an image, media file, etc from someone else’s server in one of your own pages as if it were your own. Obviously, as a webmaster, there are plenty of times when you don’t want people doing that. You’ll almost certainly have seen examples where someone has linked to one image on a website, only for a completely different, “nasty” one to be shown instead. So, how is this done?

It’s pretty simple really. All it takes are a couple of RewriteCond statements in your .htaccess file.

RewriteCond statements are as they sound - conditional statements for RewriteRules. The basic format for a RewriteCond is RewriteCond test_string cond_pattern. For our purpose, we will set the test_string to be the HTTP_REFERER. If the test string is neither empty nor our own server, then we will serve an alternative (low bandwidth) image, which tells the person who is hotlinking off for stealing our bandwidth.

Here’s how we do that:

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(www\.)?somesite.com/.*$ [NC]
RewriteRule \.(gif|jpg|png)$ http://www.somesite.com/nasty.gif [R,L]

Here, the RewriteRule will only be performed if all the preceeding RewriteConds are fulfilled. In the second RewriteCond, [NC] simply means “No Case”, so it doesn’t matter whether the domain name was written in upper case, lower case or a mixture of the two. So, any requests for gif, jpg or png files from referers other than somesite.com will result in your “nasty” image being shown instead.

The [R,L] in the RewriteRule simply means “Redirect, Last”. So, the RewriteRule will visibly redirect output to “nasty.gif” and no more RewriteRules will be performed on this URL.

If you simply don’t want the hot linkers to see any image at all when they hot link to your images, then simply change the final line to RewriteRule \.(gif|jpg|png)$ - [F]. The - means “don’t rewrite the requested URL”, and the [F] means “Forbidden”. So, the hot linker will get a “403 Forbidden message”, and you don’t end up wasting your bandwidth.

Conclusion

mod_rewrite is an incredibly handy tool to have in your arsenal. This article only scratched the surface of what is possible with mod_rewrite, but should have given you enough information to go out and start mod_rewriting history yourself!

References

Apache module mod_rewrite - Apache’s big long document about the mod_rewrite module.

The Definitive Guide to Apache mod_rewrite - If you’re serious about learning how to use mod_rewrite and need more detail than you got in this article, then I can sincerely recommend buying The Definitive Guide to Apache mod_rewrite.